在对岸桥结构进行地震反应时程分析时，瑞利阻尼系数在很大程度上影响计算的精度． 文中考虑了地震动的频谱特性和结构自身的频率特性，提出一种改进的阻尼系数的计算方法，使计算得到的阻尼系数更合理． 采用不同的方法计算得到不同阻尼系数，并将这些阻尼系数分别设置在岸桥结构动力时程分析中，所得结果同振动台地震模拟试验所得的试验值进行了比较． 结果显示:在不同的地震波激励下，当数值计算结果与试验值最接近时，其阻尼系数计算所采用的不是同一种方法;改进后的方法得到的阻尼系数能使不同地震激励下岸桥结构时程计算结果较好地符合试验结果．

As the Ｒayleigh damping coefficient remarkably influences the time-history analysis accuracy of the seis-mic response of quay crane structures，an improved calculation method of Ｒayleigh damping coefficient is proposed．In this method，both the spectrum characteristics of the ground motion and the frequency characteristics of the structure itself are taken into consideration，which makes the calculation more reasonable． Then，a series of dynam-ic time-history analyses of quay crane structures are performed by using different calculation methods of damping co-efficient，and the results are compared with those obtained by the shaking table test． It is found that，under differ-ent seismic wave excitations，when the numerical calculation results are closest to the test ones，different damping coefficient calculation methods are adopted; and that the time-history calculation results of quay crane structures ob-tained by the improved method under various seismic response accord well with the experimental ones．